Nanoparticle Applications and Uses

Nanoparticles have one dimension that measures 100 nanometers or
less. The properties of many conventional materials change
when formed from nanoparticles. This is typically because nanoparticles have a
greater surface area per weight than larger particles which causes them
to be more reactive to some other molecules.

Nanoparticles are used, or being evaluated for use, in many fields. The list
below introduces several of the uses under development.

Nanoparticle Applications in Medicine

The surface change of
protein filled nanoparticles has been shown to affect the ability of
the nanoparticle to stimulate immune responses. Researchers are thinking
that these nanoparticles may be used in inhalable vaccines.

Researchers at Rice University have demonstrated that cerium oxide nanoparticles
act as an antioxidant to remove oxygen free radicals that are
present in a patient's bloodstream following a traumatic injury. The
nanoparticles absorb the oxygen free radicals and then release the
oxygen in a less dangerous state, freeing up the nanoparticle to absorb
more free radicals.

Researhers are developing ways to use carbon nanoparticles called
nanodiamonds in medical applications. For example
nanodiamonds with protein
molecules attached can be used to increase bone growth around
dental or joint implants.

Nanoparticle Applications in Manufacturing and Materials

A synthetic skin, that may be used in prosthetics, has been demonstrated with both self healing capability
and the ability to sense pressure. The material is a composite of
nickel
nanoparticles and a polymer. If the material is held together
after a cut it seals together in about 30 minutes giving it a self
healing ability. Also the electrical resistance of the material
changes with pressure, giving it a sense ability like touch.

Silicate nanoparticles can be used to provide a barrier to gasses (for
example oxygen), or moisture in a plastic film used for packaging. This could
slow down the process of spoiling or drying out in food.

Zinc oxide
nanoparticles can be dispersed in industrial coatings to protect wood, plastic, and
textiles from exposure to UV rays.

Silver nanoparticles
in fabric are used to kill bacteria, making clothing odor-resistant.

Nanoparticle Applications and the Environment

Researchers are using photocatalytic copper tungsten oxide
nanoparticles to
break down oil into biodegradable compounds. The nanoparticles are
in a grid that provides high surface area for the reaction, is activated
by sunlight and can work in water, making them useful for cleaning up
oil spills.

Nanoparticle Applications in Energy and Electronics

Researchers have used nanoparticles called nanotetrapods studded with nanoparticles of carbon to develop
low
cost electrodes for fuel cells. This electrode may
be able to replace the expensive platinum needed for
fuel cell catalysts.

Researchers at Georgia Tech, the University of Tokyo and Microsoft
Research have developed a method to print prototype circuit boards using
standard inkjet printers.
Silver
nanoparticle ink was used to form the conductive lines needed in
circuit boards.

A
catalyst using platinum-cobalt nanoparticles is being developed for
fuel cells that produces twelve times more catalytic activity than pure
platinum. In order to achieve this performance, researchers anneal nanoparticles
to form them into a crystalline lattice, reducing the spacing between
platinum atoms on the surface and increasing their reactivity.

Researchers have demonstrated
that sunlight, concentrated on nanoparticles, can
produce steam with high energy efficiency. The "solar
steam device" is intended to be used in areas of
developing countries without electricity for
applications such as purifying water or disinfecting
dental instruments.

A lead free solder reliable enough for space missions and
other high stress environments using
copper nanoparticles.